Parallel ruler



NITED STATES PATENT OFFICE,

COLEMAN A. TERRY, or COLUMBUS, onro.

PARALLEL RULER.

$PECIFICATION forming part of Letters Patent No. 455,779, dated July 14, 1891.

Application filed January 24, 1891. Serial No. 378,970. (No model.)

To all whom it may concern;

Be it known that I, COLEMAN A. TERRY, a citizen of the United States, residing at Golumbus, in the county of Franklin and State 5 of Ohio, have invented a certain new and useful Improvement in Drawing-Instruments, of which the following is a specification;

My invention relates to drawing-instruments, and has particular relation to that T class of drawing-instruments known as liners.

The objects of my invention are to produce a superior form of drawing-instrument of this class by means of which a lining-ruler may I be made to travel a uniform distance at the completion of each line; to provide in connection therewith means for adjusting or limiting the movement of the ruler; to provide for the retention of the ruler in the new positionim- 2o parted thereto; to so construct the device as to support the ruler at the desired angle from the bed-plate, and to so construct and arrange said device as to insure speed and accuracy. These objects I accomplish in the manner 2 5 illustrated in the accompanying drawings, in

which- Figure 1 is a plan 'view of myimproved instrument. Fig. 2 is a side elevation thereof. Fig. 3 is a transverse section on line x 00 of 0 Fig. 1. Figs. 4 and 5 are similar views taken,

respectively, on lines y y and z z of Fig. 1.

' Similar letters refer to similar parts throughout the several views.

a. represents a flat rectangular metallic bedplate, provided on its upper side ad oining each of its ends and near one of the lateral edges thereof with projecting lugs or keepers a.

T) represents a ruler-supporting rod, which,

40 as shown, is of a length greater than the length of the bed-plate a, and which bears movablyin suitable guid eways or holes formed in said lugs a. Thissliding rod 1) is shown in the drawings for the sake of clearness with a portion of its body broken away. Rigidly connected with the central portion of the rod -b are the arms of the bifurcated end of a protractonplatecxwhich extends outwardly from said rod at right angles therewith, as shown. This projectingplate c is so bent as to bring the under side of its outer disk-shaped portion approximately in a line with the upper surface of the bed-plate. To the under side of the outer disk-shaped end or head 0 of the arm 0 is adjustably connected by a clampingscrew 0 one end of a suitable ruler d, the under side of said ruler being in line or flush With the under surface of the bed-plate a. Upon the upper surface of the plate-head c and adjoining the curved end thereof, are formed radial scale marks or lines c The ruler d, as shown in the drawings, is provided with a central indicating-line d, which is adapted to be brought into alignment with the desired one of the scale-marks c 6 5 6 represents a sliding plate, which ismov- 4 ably supported upon-the bed-plate a, near the center of the length thereof, beneath the rod b. This plate ehas formed therein,near each end thereof, a short longitudinal, slot e, through each of which passes loosely, as shown, a short vertical screw or pin 6 which is provided with an enlarged head and which has its lower end fixed in the bed-plate.

g represents a rocking arm, which extends outwardly at right angles with the rod 1), and which has its inner and thickened end por tion pivotally supported upon a.pivot-pin g, which projects upwardly from the upper side of the center of the length of the sliding bar e. The upper thickened portion of the arm g is provided, as shown, with a central groove or seat g of such width and depth as to admit of the rod 1), or the lower half thereof, passing theret-hrough without contact with the arm-body when the latteris projecting at right angles from said rod. The outer end of the arm g is provided with a suitable finger piece or button 9 Formed with the sliding plate 6 in the forward half thereof is an out- 0 wardlyrprojecting arm f, which is provided on its outer end with an upwardly-projecting stop finger or lug f. Projecting upwardly from the upper'surface of the plate a, a short distance in front of the outer end portion of 5 the plate-arm f, is a screw-supporting lug t, the central screw-hole of which supports a horizontal stop-screw 7c, the forward end of which is provided with a disk-shaped head or finger piece 7d, the latter having its periphery notched, as shown at k 70 represents an approximately U-shaped spring-catch, which is formed of spring-wire, has its end portions secured to the upper sur- ISO face of the bed-plate, and has its centralportion engaging with the desired one of the notches k of the screw-head Engraved or otherwise formed upon the upper face ofqthe plate a and extending longitudinally between the lug i and arm f is a scale m, graduated to represent the desired distance-divisions.

The rear end of the plate 6 is connected by a coiled spring 6 with a suitable projection e on the upper face of the bed-plate a, beneath the rod b, the tension of said coiled spring being such as to normally hold the forward end of the plate-slots 6 against the stop-pins e n represents a cam-shaped body recessed in its under side and pivoted at one end at a point near the forward end of the bed-plate CL, and near the rod 19. The outer and upwardly extended end of the cam n is rounded, as shown, said rounded end or head being pressed into frictional contact with the rod 1) by the tension of a spring-wire n. This spring-wire n has its end coiled about and secured to a pivot-pin 02 which secures, as shown, the cam n to the bed-plate, the connection of the spring n being made with said pin within the recessed portion of the cam, and the outwardly extending end of said spring engaging with a small opening in the head of the cam, as shown in Fig. 5 of the drawings. The tension of the spring at is such as to cause its outwardly-proj ecting arm to normally press the head of the cam into engagement with the rod b, by which means, as hereinafter described, said cam acts as a brake for said rod.

\Vhen it is desired to use my improved instrument for producing section or other equidistant lines, theinstrument is first set to produce the desired space between the lines to be drawn by pressing the arm f forward until its forward edge is in line with or opposite that graduating-mark of the scale m which indicates the desired distance-division. The screw his then turned until its outer end comes in contact with the finger-piece f of the arm f, the end of said screw thus being set to limit the forward movement of the arm f to the desired distance. The rule or straightedge at is then turned to the desired angle with the protractor-head c, the degree of said angle being indicated by the indicating-line d of the ruler, which is brought into line with the desired scale-mark 0 These parts having been set, as described, and the bedplate so laid as to bring the ruler d in the desired position upon the drawing-paper, the outer edge of the ruler d is utilized as a guide for the lining-instrument in one hand of the operator, while with his remaining hand he presses forward upon the outer end of the rocking arm 9 as each line is completed. This movement of the arm g will result, through the binding of its grooved head 9 therewith, in a forward movement of the rod 1) and sliding plate e, this forward movement being limited only by the contact of the arm f and screw 7c. The bearing of the head of the cam-n against the rod 12 being on one side of the center of said cam-head and the pressure thereof being toward the rear end of said rod, it will be seen that the forward movement of the rod 1), above described, will not be interfered with by said cam-head,but the latter will operate to automatically prevent the return of the rod to its old position, thus resulting in the shifting of the ruler d at each pressure of the arm f to a new position. As the forward movement of the sliding plate and rod is completed the former automatically returns to its former position through the action of the spring 6 From the construction shown and de scribed it will not only be seen that the production of equidistant lines at any angle is facilitated, but that the rod 19, being pivoted in the hearings to", admits of the ruler and its protractor-plate bein g elevated from the work, when desired, for examination or other purposes.

It will be seen from the above description that my improved drawing-instrument is of simple and substantial construction and positive in its operation, and that the same may be produced at a reasonable cost of manufacture.

It is obvious that the herein-shown instrument maybe utilized in surface-shading,section-lining, &c., and will result in the speedy production of lines of such uniform arrangement as to greatly add to the appearance of the drawing.

In case it is desired to produce shade or other lines, the distance between which it is desired to gradually increase or decrease, it is obvious that the operator may accurately produce such lines by turning the screw-head 70' an increased ondiminished distance at the completion of each line. In so doing the operator is enabled to compute the desired accurate gradations by the number of clicks resulting from the contact of the U-shaped spring and the notches k It is obvious from the means shown and described that in setting the device for the production of lines the operator is not confined to any standard scale or fixed division thereof, but that he may by turning the screw 70 set the device for any division of distance embraced by said screw movement.

Having now fully described my invention, what I claim, and desire to secure by Letters Patent, is-

'1. In a drawing-instrument, the combination, with the bed-plate a, asliding rod I), j ournaled thereon,.and a protractor-plate connected with said rod, of a ruler d, adjustably connected with the protractor-head, and means for moving said rod forwardly upon said plate, substantially as specified.

2. In a drawing-instrument, the combination, with the bed-plate a, a sliding rod 1), j ournaled upon said bed-plate, a protractor-plate connected with said rod, and a ruler adjust- ITO ably connected with said protractor-plate, of a pivoted rocking arm g, through which said rod passes loosely, and a spring-actuated cam n, as described, pivoted adjacent to said rod 1) and bearing against the latter on one side of its center, substantially as described.

3. In a drawing-instrument, the combination, with the bed-plate a, sliding rod b, journaled upon said bed-plate, a protractor-head rigidly connected with said rod, and a ruler d, adj ustably connected with said protractorhead, of a spring-actuated sliding plate 6, having slots 6 and stop-pins e projecting therethrough, rocking arm g, pivotally supported upon said sliding plate and loosely embracing rod 1), as described, and a springactuated cam '11, one side of its center bearing against the rod 1), substantially as and for the purpose specified.

4. In a drawing-instrument, the combination, with the bed-plate a, sliding rod 12, journaled upon said bed-plate, a protractor-head rigidly connected with said rod, and a ruler d, adj ustably connected with said protractorhead, of a spring-actuated sliding plate e,

having slots 6 and stop-pins e projecting therethrough, arm f, projecting from plate 6,

rocking arm g, pivotally supported upon plate e and loosely embracing the rod b, stop-screw k, adjustably supported, as described, from the plate a in front of the arm f, a scale m in said bed-plate, and a spring-actuated cam bearing on one side of its center against the rod 1), as described, substantially as and for the purpose specified.

5. In a drawing-instrument, the combination, with the bed-plate a, sliding rod 12, journaled upon said bed-plate, a protractor-head rigidly connected with said rod, and a ruler d, adj ustably connected with said protractorhead, of a spring-actuated sliding plate 6, looking arm g, pivotally supported on said sliding plate and loosely embracing rod 1), as described, arm f, projecting from the plate 2, stop-screw 7c, adj ustably supported, as described, from the plate a in front of the arm f, notches 70 in the periphery of said stopscrew head, and spring-wire k adapted to engage with said notches k substantially as specified.

COLEMAN A. TERRY.

In presence of' BARTON GRIFFITH, A. N. HILL. 

